Mira Sport shower not heating up correctly

gavtro · Oct 13, 2024

Hello.

We have a very old (the instruction manual is dated 2006!) Mira Sport 9.0kw shower.

A while ago it developed a leak which was fixed by replacing the flow valve assembly (including the switch).

However, since then, the shower has failed to heat-up correctly. To get hot water after switching on, instead of it being automatic after a few seconds, we have to turn both the pressure and temperature dials down then up in order for the water to heat. And even then, pressure will seem a little low, plus the low flow warning light will be illuminated.

Taps and toilet flush will have an occasional 'fog horn' sound too. We replaced the ball valve in the loft but this doesn't seem to have had any effect.

It's probably only something minor that needs correcting but it's driving us crazy. Any ideas what could be the problem?

Thanks in advance.

Andy™ · Oct 13, 2024

one of the heating elements has failed

gavtro · Oct 13, 2024

We did wonder about that but thought it would have been too much of a coincidence for two parts to fail at once, unless, of course, the flow valve then caused the heating tank unit to fall (or maybe the other way around)?

So, replace the heater tank? Why would it heat up, though, after adjusting the dials if an element has failed?

Could the new flow valve be faulty? (maybe, despite it saying it was the 9.0kw version, perhaps it wasn't?)

When you order the replacement flow valve, there's a disclaimer:

NOTE FOR PRE 2005 Sport Models

Due to a modification by Mira, if a flow valve or switching assembly is required, the following 3 items would need to be replaced:

But, as mentioned, we believe our model to be a 2006, maybe later, so the above shouldn't affect us?

Sorry for all the questions within questions!

binky · Oct 13, 2024

average shower life is around 10 years, so probably due a new one.

SPECIAL LOCATION · Oct 13, 2024

From my experience, with a wide range of makes / models of electric shower, as Binky suggests, if they are over 10years old then generally its not economically worthwhile attempting to repair them...

As the time spent faffing around locating a part, replacing a part plus the cost of the part itself is better spent investing in a new shower.

The ball-valve feeding the loft tank will have no relevance to an electric shower as the shower should be connected directly to the incoming rising cold water main at street pressure.

Electric shower have two elements inside the water heating chamber...
As Andy said it sounds like one of the elements has failed..

Time to get a new shower.